1201 S. Hope
At 1201 S. Hope, the shoring redesign coordinated tieback rows near the Metro light rail at Pico Station. Revit helped lay out cased tieback shafts at a reentrant corner; the contractor tested the anchors.
Specialty structural engineering
Tieback Shoring Design
Anchored shoring that leaves working space inside an excavation, with layouts that account for property rights, utilities, and nearby foundations.
How it works
How tiebacks support a shoring wall
Tiebacks are anchors drilled from a shoring wall into the ground behind it. They transfer lateral load away from the excavation through the wall, walers or other connection details, and the ground. A workable layout depends on anchor geometry, capacity criteria, installation access, and the ground or infrastructure the anchors pass through.
Tiebacks can preserve open space inside a deep cut, but they may extend beyond the site. Property agreements, underground utilities, neighboring foundations, and transit facilities can rule out a proposed row or require a different support arrangement. Installation and testing also have to fit the excavation stages.
Site conditions
Tieback shoring keeps the excavation open for construction
Tiebacks support a shoring wall from the ground behind it, leaving more space inside the excavation for equipment and foundation work. Cefali designs anchor layouts around property rights, neighboring basements, tunnels, and utilities that may limit where drilling is possible.
- Rights and boundaries
- Property lines and available agreements can determine whether anchors can extend beyond the site.
- Underground conflicts
- Basements, tunnels, utilities, and other buried structures can limit anchor length or angle.
- Movement and staging
- Anchor rows, testing, preload, and excavation stages must be coordinated with wall performance and construction access.
Engineering services
Tieback layout and shoring design
Cefali & Associates designs tiebacks as part of the shoring system, coordinating anchors with piles, walers, adjacent facilities, and the permanent structure.
- Anchor feasibility
- Property limits, buried structures, and drilling access determine where anchors can be considered and where another support may be needed.
- Support design
- The wall, anchor rows, and their connections work together to carry loads at each planned excavation stage.
- Alternatives to tiebacks
- Rakers and internal braces are options where anchors cannot be installed. Their layout also needs space for excavation, foundations, and access.
We agree the drawings, calculations, and support during construction with you in the proposal.
Design considerations
Property rights and buried structures limit anchor locations
An anchor can extend beneath neighboring land even when the wall sits inside the property line. The design needs both the available property rights and the locations of utilities, foundations, and tunnels that limit drilling.
- Rights and obstructions
- An easement may allow an anchor beyond the boundary, but an existing basement, utility, or tunnel can still block its path.
- Wall connection
- Pile, waler, and anchor details need a continuous load path, especially where existing walls or limited drilling positions interrupt a regular layout.
- Support where tiebacks cannot fit
- Rakers or cross-lot braces may support the wall where tiebacks cannot fit. They take up space inside the excavation and need to be designed around foundation work and construction access.
In practice / The Grand
The design in practice.
At The Grand in Downtown Los Angeles, short anchors were coordinated near an active tunnel. Along another edge, a multi-row waler system transferred forces to locations where tiebacks could be installed because an existing wall blocked drilling at some piles.
See the The Grand projectMore project examples
Intuit Dome
At the Intuit Dome entrance tunnel, tieback agreements were unavailable. Cross-lot braces supported the excavation from within the site and were placed above truck traffic.
Related project work
Projects involving tieback shoring
See the systems, site conditions, and construction details from these projects.
Before you begin
Common questions
What if tiebacks cannot cross a property line?
The team may need to evaluate internal rakers, cross-lot bracing, cantilever support, or a different wall layout. The choice depends on the excavation, loads, and available working space.
Are tunnel and utility locations needed early?
Yes. Records of underground facilities help the team check anchor locations before developing a layout that could conflict with them.
Does a tieback design give the project permission to drill outside the property?
No. The engineering design and the right to use off-site property are separate. The owner and appropriate advisers need to establish the property rights or agreements available for the proposed anchor geometry.
Does an anchor crossing a boundary need an agreement?
Whether an agreement is required depends on the property and jurisdiction. The project team should establish rights before relying on off-site anchor geometry.
Who tests tiebacks?
At 1201 S. Hope, the shoring contractor tested the tiebacks. The specifications and construction scope for each project identify who performs the tests and the required testing.
Discuss your project
Tell us what you are planning.
Send the drawings, reports, and site information you already have, along with your schedule and the work you need help with. You do not need a complete design package to get in touch.
- Property survey and known easements or no-drill zones
- Excavation sections and shoring wall geometry
- Geotechnical report and groundwater information
- Records for nearby foundations, utilities, and tunnels